1. EquiBiotech Inc-Research Services in Farm Animal Breeding, 19 Gravias Street P.O. Box 54645, Thessaloniki, Greec e
2. Veterinary Research Institute, Hellenic Agricultural Organization, 57001 NAGREF Campus, Thermi, P.O. Box 60272, Thessaloniki, Greece
3. Alexander Technological Educational Institute, Department of Animal Production, P.O. Box 141 Sindos, Thessaloniki, Greece
4. Ss. Cyril and Methodius University in Skopje, Faculty of Veterinary Medicine, Institute of Reproduction, Lazar Pop Trajkov 5-7, 1000 Skopje, R. Macedonia